Anna Gosline Implants buried deep inside the brain may provide the best hope yet for vision-restoring bionic eyes. Most visual prosthetics rely on implants behind the retina. These stimulate surrounding nerve tissue to generate points of light, called phosphenes, in the mind's eye. Such prosthetics require a detailed map of where phosphenes appear in response to electrical stimulation. Once this map is complete, digital images, captured by a camera, can be converted to electrical pulses that produce multiple points of light, allowing a blind person to "see" simple shapes. In patients with severe eye trauma, however, there may not be enough surviving retinal neurons to stimulate. Or a patient's retinas may simply have degenerated over time. An alternative is to place implants directly in the brain, within the visual cortex. But this is a large and complexly folded part of the brain, making access and mapping of the visual field a serious challenge. Now John Pezaris and colleague R. Clay Reid, both at Harvard Medical School in Boston, US, have shown that phosphenes can be produced by stimulating the lateral geniculate nucleus (LGN) – an area deep in the centre of the brain that relays visual signals from the retina to the cortex. © Copyright Reed Business Information Ltd.

Keyword: Vision; Robotics
Link ID: 10204 - Posted: 06.24.2010

Heidi Ledford A migraine is not just a headache, it is an über-headache — a pounding, queasy, searing pain that can incapacitate its victims for hours on end. And as if the pain weren't bad enough, sufferers were also thought to show diminished memory and verbal skills. But new research now suggests that although migraines are sometimes associated with diminished cognitive skills, sufferers may in fact show less memory loss as they age than those who are migraine-free. The results are puzzling, admits Amanda Kalaydjian of the National Institute of Mental Health in Bethesda, Maryland, who led the study. "We originally hypothesized that migraineurs would be doing worse," she says, "so I was really surprised." More than 28 million people in the United States suffer from migraines, and women are three times more likely than men to have the condition. The cause is still unknown, and different theories have blamed nervous-system malfunctions, chemical imbalances, over-reactive blood vessels, or a combination of factors. ©2007 Nature Publishing Group

Keyword: Pain & Touch; Learning & Memory
Link ID: 10203 - Posted: 06.24.2010

Bob Holmes Nepotism is known to be important in chimpanzee society, but male chimps' ability to cooperate extends beyond family connections, new research reveals. This extra level of sophistication is yet another way in which the social behaviour of chimps parallels that of humans. Kevin Langergraber, an anthropologist at the University of Michigan in Ann Arbor, US, and colleagues recorded alliances, meat-sharing and other cooperative behaviour among 41 male chimps in Kibale National Park, Uganda. The team also genotyped each animal to measure how closely they were related. Over a period of seven years, and over 5000 hours of observations, they observed 753 aggressive coalitions - where they cooperated to fight enemies – and 421 instances of meat sharing. Chimps who shared a mother were far more likely to cooperate with each other. In contrast, there was no evidence that the same applied to chimps with a shared father. This is probably because fathers do not stay with their offspring, so a chimp has no easy way to recognise his paternal brothers. © Copyright Reed Business Information Ltd

Keyword: Evolution
Link ID: 10202 - Posted: 06.24.2010

By JOHN CLOUD Are psychedelics good for you? It's such a hippie relic of a question that it's almost embarrassing to ask. But a quiet psychedelic renaissance is beginning at the highest levels of American science, including the National Institute of Mental Health (NIMH) and Harvard, which is conducting what is thought to be its first research into therapeutic uses of psychedelics (in this case, Ecstasy) since the university fired Timothy Leary in 1963. But should we be prying open the doors of perception again? Wasn't the whole thing a disaster the first time? The answer to both questions is yes. The study of psychedelics in the '50s and '60s eventually devolved into the drug free-for-all of the '70s. But the new research is careful and promising. Last year two top journals, the Archives of General Psychiatry and the Journal of Clinical Psychiatry, published papers showing clear benefits from the use of psychedelics to treat mental illness. Both were small studies, just 27 subjects total. But the Archives paper--whose lead author, Dr. Carlos Zarate Jr., is chief of the Mood and Anxiety Disorders Research Unit at NIMH--found "robust and rapid antidepressant effects" that remained for a week after depressed subjects were given ketamine (colloquial name: Special K or usually just k). In the other study, a team led by Dr. Francisco Moreno of the University of Arizona gave psilocybin (the merrymaking chemical in psychedelic mushrooms) to obsessive-compulsive-disorder patients, most of whom later showed "acute reductions in core OCD symptoms." Now researchers at Harvard are studying how Ecstasy might help alleviate anxiety disorders, and the Beckley Foundation, a British trust, has received approval to begin what will be the first human studies with LSD since the 1970s. © 2007 Time Inc.

Keyword: Drug Abuse
Link ID: 10201 - Posted: 06.24.2010

By JOHN SCHWARTZ and BENEDICT CAREY The video testament that Cho Seung-Hui mailed to NBC during the intermission in his killing spree offers a compelling peek into the troubles that shaped a gunman, experts in forensic psychology say. The clips suggest a person with holes in his soul, who lacked features like the emotional control and empathy for others that keep a lid on the violent impulses anyone might have. But can grainy, YouTube-ish video snippets offer real insight into the nature of Mr. Cho’s mental illness? A solid diagnosis requires time and access to the patient, whose history can be as important as his actions; and most people with mental illness are far more likely to harm themselves than others. There is a universe of possible labels, and the exercise can be an empty one, said Robert Hare, an expert in violent behavior who has been a consultant to the F.B.I. “Diagnoses are ill advised if they are made too quickly,” said Dr. Hare, who created one of the most authoritative models for detecting psychopathy. “After-the-fact explanations of this sort can go in about a thousand different directions.” Experts who have watched the videos say that while the picture may yet change, they did see sentiments and thought that hint at Mr. Cho’s mental landscape. Their opinions coalesce around a handful of conditions with names like “psychotic depression” and “avoidant personality disorder” and “schizophrenia-paranoid type.” Copyright 2007 The New York Times Company

Keyword: Aggression
Link ID: 10200 - Posted: 06.24.2010

By STEPHANIE SAUL For many women, a birth control pill that eliminates monthly menstruation might seem a welcome milestone. But others view their periods as fundamental symbols of fertility and health, researchers have found. Rather than loathing their periods, women evidently carry on complex love-hate relationships with them. This ambivalence is one reason that a decision expected next month by the Food and Drug Administration has engendered controversy. The agency is expected to approve the first contraceptive pill that is designed to eliminate periods as long as a woman takes it. Doctors say they know of no extra risk to the new regimen, but some women are uneasy about the idea. “My concern is that the menstrual cycle is an outward sign of something that’s going on hormonally in the body,” said Christine L. Hitchcock, a researcher at the University of British Columbia. Ms. Hitchcock said she worries about “the idea that you can turn your body on and off like a tap.” That viewpoint is apparently one reason some already available birth control pills that can enable women to have only four periods a year have not captured a larger share of the oral contraceptive market. “It’s not an easy decision for a woman to give up her monthly menses,” said Ronny Gal, an analyst at Sanford C. Bernstein & Company. Copyright 2007 The New York Times Company

Keyword: Hormones & Behavior
Link ID: 10199 - Posted: 06.24.2010

14-year-old Ashley Chapin goes through the stresses of a regular teenager: feeling the peer pressure about what to wear, how to dress, how to do her hair. She has a great relationship with her mom, but admits it sometimes gets ugly. "We're at the store, right, and we're shopping around. And I'm looking at some black stuff, and she sees this skirt that she wants me to buy. And I'm like 'Oh my god, it's pink, I don't want to buy it,'" she says. Luckily her mom, neuroscientist Sheryl Smith, is an expert on teenage mood swings. She discovered that in female mice going through puberty, a hormone called THP that normally calms nerve cells, excites them instead. "It's the first time that we've seen a very specific effect of a hormone at puberty that has a different effect than it has in the adult," says Smith, who is an associate professor at State University of New York Downstate Medical Center. THP, tetrahydroprogesterone, is a steroid that's derived from progesterone, a familiar hormone that has multiple effects in the reproductive and nervous systems, among others. Smith studied the effects of THP produced in the brain, and up to this time, THP has been seen as a stress-reducer. "It's released during stress," she says, "so it's believed that one of its functions is to help you calm down after a period of stress." Smith says that in high enough doses in adults, THP has been shown to work as a tranquilizer and anesthetic. © ScienCentral, 2000-2007.

Keyword: Hormones & Behavior; Emotions
Link ID: 10198 - Posted: 06.24.2010

Jennifer Viegas, Discovery News — Stink bug mating is so lengthy and lively that egg-colonizing parasites actually eavesdrop on it to their advantage, according to a new study. The findings represent the first discovery of a parasite, in this case a wasp, eavesdropping on the vibratory sexual signals of another insect. Since some farmers use the parasite to control populations of stink bugs that feed on crops such as soybeans, the discovery might lead to better, natural pest removal methods. It is possible the wasp evolved the ability to detect stink bug mating, since other creatures — including people — can't. "Humans cannot hear stink bug vibratory songs without special equipment," lead author Raul Laumann told Discovery News. Laumann, a scientist at Embrapa Genetic Resources and Biotechnology in Brazil, explained that both male and female brown Neotropical stink bugs vibrate muscles linked to their abdomen and thorax, before and during copulation. Laumann and his colleagues obtained stink bug nymphs from a Brazilian laboratory colony. The researchers set the stage for mating by rearing the insects on a nutritious diet of sunflower seeds, soybeans, raw peanuts and green beans in a comfortable, humidity-controlled environment. © 2007 Discovery Communications Inc.

Keyword: Sexual Behavior; Hearing
Link ID: 10197 - Posted: 06.24.2010

Emma Young High temperatures can make an Australian lizard that is genetically male develop into a female. The finding throws new light on how sex is determined in reptiles. For most reptiles, a gene on a sex chromosome triggers an embryo to develop as either a male or a female. In some species, males have an X and a Y chromosome, while females are XX, as in mammals. In other species of lizards, males are ZZ while females are ZW, as in birds. But for a third group of reptiles, which includes all crocodiles, alligators and marine turtles, temperature, rather than a gene on a sex chromosome, triggers either male or female differentiation. Extreme low or high temperatures generally lead to more females. Now a team led by Alex Quinn at Canberra University in Australia has found that the central bearded dragon (Pogona vitticeps) is susceptible to both types of sex trigger, and that temperature can override its genetic gender. When the team incubated eggs at relatively high temperatures – between 34°C and 37°C – the majority of embryos that had ZZ sex chromosomes (genetically male), hatched as females. The team thinks the bearded dragon represents a transitional form, in evolutionary terms, between the two main methods of sexual determination. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior
Link ID: 10196 - Posted: 06.24.2010

Researchers have devised a clever way to activate neurons in a living mouse by shining light on the surface of the animal's brain. The “light switch” that turns neurons on is actually a light-sensitive protein that is produced by algae. When this protein is genetically engineered into the neurons of living mice, researchers can precisely trigger those neurons with light, causing them to generate electrical impulses. The scientists who developed the new method believe it will change how researchers map the function of brain circuits in living animals. “We believe that this light-induced activation technique is a major technical breakthrough in the functional analysis of neural circuitry,” said the leader of the research team, Michael Ehlers, a Howard Hughes Medical Institute researcher at Duke University Medical Center. “This technique will soon become the standard method for these types of experiments.” The researchers published a research article describing the new technique in the April 19, 2007, issue of the journal Neuron. The research team included Ehlers and Duke colleagues Benjamin Arenkiel, Guoping Feng and George Augustine. Other co-authors were from the University of Coimbra and the Gulbenkian Science Institute in Portugal, and from Stanford University. © 2007 Howard Hughes Medical Institute

Keyword: Miscellaneous
Link ID: 10195 - Posted: 06.24.2010

The cause of high blood pressure may lie within the brain, rather than with problems relating to the heart, kidneys or blood vessels, research suggests. Scientists at Bristol University say the findings could lead to new ways of treating the condition, which affects about one in five Britons. They isolated a protein, JAM-1, in the brain which appeared to trap white blood cells, obstructing blood flow. This can cause inflammation and result in poor oxygen supply to the brain. Professor Julian Paton and colleagues believe these, in turn, trigger events that raise blood pressure, the journal Hypertension reports. Their studies in rats show JAM-1 is linked to raised blood pressure, but the exact mechanisms behind this are still unclear. They are now looking at the human brain to understand more. Professor Paton explained: "The future challenge will be to understand the type of inflammation within the vessels in the brain, so that we know what drug to use, and how to target them. JAM-1 could provide us with new clues as to how to deal with this disease. We are looking at the possibility of treating those patients that fail to respond to conventional therapy for hypertension with drugs that reduce blood vessel inflammation and increase blood flow within the brain." (C)BBC

Keyword: Stress
Link ID: 10194 - Posted: 04.19.2007

Katharine Sanderson Red apes have an easy life: their preferred method of getting from one tree to the next in the jungle not only keeps them safe from harm, but also saves them a lot of hard work. A detailed investigation into how orangutans use the sway of branches to propel themselves from tree to tree shows that it is way more efficient than climbing down one tree and up the next. Susannah Thorpe at the University of Birmingham, UK, and her colleagues studied video footage of Sumatran orangutans. These are the largest primates known to live exclusively in the tree canopy, in part because of the Sumatran tiger and other predators that await them on the ground. Crossing the gaps between trees is crucial for these animals. But the shortest gaps are also where the branches are thinnest and most flexible. "If you put an orangutan on a flexible branch it's going to sink fast," Thorpe says. Orangutans have a strategy to avoid this problem: they go to stronger vertical branches nearer the tree trunk and, by shifting their body weight, sway them until the thin branches of the next tree are within reach. They can then either move over directly or use the thin branch to pull a stronger branch of the next tree towards themselves and cross over that way. ©2007 Nature Publishing Group

Keyword: Evolution
Link ID: 10193 - Posted: 06.24.2010

A commercial surgery robot that will allow doctors to perform microscopic operations on the brain using the most vivid visuals yet has been unveiled by Canadian scientists and engineers. NeuroArm is the first surgical robot to be compatible with MRI (magnetic resonance imaging), its makers claim. This will enable neurosurgeons to perform their riskiest work while patients lie within an MRI machine, giving a clear 3D picture of even the smallest nerves. However, doctors are still on hand to intervene if serious complications arise. The machine will let doctors use surgical techniques on afflictions such as brain tumours that unaided human surgeons are simply not dexterous enough to perform, says Garnette Sutherland, a neurosurgeon at the University of Calgary who heads the project. It is major step beyond the traditional view of just doctors and nurses operating on patients, he adds. "There's been tremendous collaboration, so we have now got in the operating room a whole host of engineers and scientists who are contributing to help make neurosurgery better," Sutherland told reporters as the robot, armed with surgical tools, fiddled with tiny objects behind him. The machine is expected to be used in its first operation this summer at Calgary's Foothills Hospital, site of the University of Calgary medical school's research facility. © Copyright Reed Business Information Ltd.

Keyword: Brain imaging; Robotics
Link ID: 10192 - Posted: 06.24.2010

By ELISSA ELY, M.D. The death report was asking the wrong questions — whether the patient had drunk four to eight glasses of water daily, whether his diet was low in saturated fats and salt. Death had not been a result of junk food; it had been a result of suicide. When it is your patient who has died, there is a fugitive quality to it: someone has fled, and you were unable to capture or return him alive. Diet and fluids are the least of the problem. My patient had been an educated man, full of yearning. He wanted a mate and a job. Schizophrenia made both hard to find. I knew about his voices, and sometimes knew what his voices told him, but had come to believe that voices and patient coexisted in a delicate yet stable ecosystem. It was a false belief. No one is immune from contemplating suicide. Demographic studies show that the population most at risk is single, urban, substance-abusing older white men with physical illness, few supports and low incomes. We memorize the characteristics in residency training and recall them in evaluations to figure out how frightened we ought to be. The criteria are so specific it’s like putting pins in a war map. By these criteria, my patient could not be found on the map (though psychosis is also a high risk factor). Copyright 2007 The New York Times Company

Keyword: Depression
Link ID: 10191 - Posted: 06.24.2010

By RICHARD PÉREZ-PEÑA With grim humor, some doctors in New York call them “frequent fliers” — addicts who check into hospital detoxification units so often that dozens of them spend more than 100 nights a year in those wards. Through its Medicaid program, New York spends far more than other states on drug and alcohol treatment, including more than $300 million a year paid to hospitals for more than 30,000 detox patients. One reason for the high cost is that $50 million is spent just on the 500 most expensive patients, at a cost of about $100,000 a person. These patients check in and out of detox wards, on average, more than a dozen times a year — a practice that experts say would not be tolerated in most states. In the state’s 2004 fiscal year, one patient was admitted to such units 26 times at 17 different hospitals around New York City, spending a total of 204 nights, Medicaid records show. In fiscal year 2005, there was one patient who spent 279 nights in detox wards, at a cost of about $300,000. New York State spends more than enough money to provide all the needed treatment, but “the dollars are being spent in the wrong settings,” said Deborah S. Bachrach, the state’s Medicaid director. In Gov. Eliot Spitzer’s campaign to overhaul Medicaid, she said, “this is very high on our agenda.” Copyright 2007 The New York Times Company

Keyword: Drug Abuse
Link ID: 10190 - Posted: 06.24.2010

By JOHN NOBLE WILFORD CHICAGO — Observed in the wild and tested in captivity, chimpanzees invite comparison with humans, their close relatives. They bear a family resemblance that fascinates people, and scientists see increasing evidence of similarities in chimp behavior and skills, making some of them think on the vagaries of evolution. For some time, paleontologists and evolutionary biologists have known that chimp ancestors were the last line of today’s apes to diverge from the branch that led to humans, probably six million, maybe four million years ago. More recent examination shows that despite profound differences in the two species, just a 1.23 percent difference in their genes separates Homo sapiens from chimpanzees, Pan troglodytes. And certain similarities between the two species, scientists say, go beyond expressive faces and opposable thumbs. Chimps display a remarkable range of behavior and talent. They make and use simple tools, hunt in groups and engage in aggressive, violent acts. They are social creatures that appear to be capable of empathy, altruism, self-awareness, cooperation in problem solving and learning through example and experience. Chimps even outperform humans in some memory tasks. Copyright 2007 The New York Times Company

Keyword: Evolution
Link ID: 10189 - Posted: 06.24.2010

By JANE E. BRODY Every so often, seemingly normal people suddenly walk out of their lives and disappear, with no recollection of who they are, where they are from or what their previous life was like. It is the stuff of fiction, but it happens in real life too. Last year a Westchester County lawyer — a 57-year-old husband and father of two, Boy Scout leader and churchgoer — left the garage near his office and disappeared. Six months later he was found living under a new name in a homeless shelter in Chicago, not knowing who he was or where he came from. Library searches and contact with the Chicago police did not help the man. His true identity was uncovered through an anonymous tip to “America’s Most Wanted.” But when he was contacted by his family, he had no idea who they were. On the fictional side is a play called “Fugue,” now on stage at the Cherry Lane Theater in New York. In it, a woman found wandering homeless in Chicago is interviewed by a psychiatrist. She does not know her name and can recall nothing about her life before landing in Chicago. The rest of this most interesting play by Leonora Thuna is an exploration of a rare but intriguing emotional disorder, known technically as dissociative fugue or dissociative amnesia. (C) New York Times

Keyword: Learning & Memory
Link ID: 10188 - Posted: 06.24.2010

By Will Dunham WASHINGTON (Reuters) - People who commit mass murders like the one at Virginia Tech university often are frustrated loners bent on revenge who blame others for their own failures, experts in such crimes said on Tuesday. When Charles Whitman shot dead 13 people from a University of Texas tower in 1966, he triggered "an age of mass murder" in the United States, said James Alan Fox, a criminal justice professor at Northeastern University in Boston. Since then, there have been about two dozen U.S. cases annually of murders with at least four victims, Fox said. The frequency of these crimes has remained steady over four decades, but the lethality has risen with the greater availability of high-powered firearms, Fox said. Authorities identified the gunman in Monday's Virginia Tech killings as student Cho Seung-Hui, 23, a South Korean who was a legal U.S. resident. They say he killed 32 people and himself. "What motivates most mass murderers is the desire for revenge. They see themselves as victims. They see injustice around them and that they've been dealt a raw deal," Fox said. © 1996-2007 Scientific American, Inc.

Keyword: Aggression
Link ID: 10187 - Posted: 06.24.2010

Associated Press — The first dozen Parkinson's patients to have holes drilled in their skulls for a novel gene therapy attempt weren't harmed — and hints at some improvement have researchers embarking on a larger study to see if the treatment really may work. Doctors reported initial results of the closely watched experiment at a neurology meeting Monday, but cautioned that it's far too soon to raise hopes. At issue: Using a nerve growth factor to try to rescue dying brain cells. Some 1.5 million Americans have Parkinson's, a disease that gradually destroys brain cells that produce dopamine, a chemical crucial for the cellular signaling that controls muscle movement. Too little dopamine causes increasingly severe tremors and periodically stiff or frozen limbs. Standard treatments can control tremors for a while but can't stop the disease's inevitable march. So scientists are hunting ways to protect remaining dopamine-producing neurons, and rescue dying ones. Previous attempts with growth factors haven't panned out. The new approach uses gene therapy — injecting a virus that carries a gene that in turn produces the growth factor neurturin — to try to get the protective protein right where it's needed. © 2007 Discovery Communications Inc.

Keyword: Parkinsons; Trophic Factors
Link ID: 10186 - Posted: 06.24.2010

Heidi Ledford A re-evaluation of clinical data suggests that although antidepressants do promote suicidal tendencies in a small percentage of children and adolescents — as widely reported a few years ago — the benefits of the drugs for the treatment of depression and anxiety disorders almost always outweigh the risks. The new study, published this week in the Journal of the American Medical Association, makes use of data that were not available when the US Food and Drug Administration (FDA) evaluated the drugs for their safety in children in 2004. The findings from that evaluation led to the placement of a so-called 'black box' warning label on antidepressants, cautioning consumers that the drugs could cause suicidal tendencies in individuals under the age of 18. Black-box warnings are the strongest alerts the agency can assign before banning a drug. After the FDA review, Jeffrey Bridge, an epidemiologist at Ohio State University in Columbus, and his colleagues worried that the negative publicity surrounding the drugs had shifted attention away from any benefit the treatments might offer to children suffering from depression and other anxiety disorders. "The black-box warning showed us that there was a risk of suicidal thinking and behaviour, but it didn't take benefit into account," says Bridge. "We wanted to balance the discussion." ©2007 Nature Publishing Group

Keyword: Depression; Development of the Brain
Link ID: 10185 - Posted: 06.24.2010